how to increase the buzzer loudness

[MARTIN FR]

Hello everyone ,

i am trying to increase the sound of the buzzer so can anyone suggest me do i ahve to increase the supply voltage or do i have to modify the dutycycle of the buzzer , i really dont ahve any idea how to achieve this without adding any audio amplifier circuit any suggestions or ideas will be really helpful for me to move forward

Thank you

pwm_volt.c

[Ole Bauck]

You can increase the duty cycle (which will increase the average voltage), or you can increase the supply voltage. Do what is easiest for you. The average voltage will determine the loudness: loudness = supply voltage * duty cycle.

[MARTIN FR]

yes i have modified the duty cycle but am still getting little audible sound only for example i want to make the buzzer beep which can audible upto 30meters approx so inorder to create that kind of loudness what i must to do can yout ell me how can i change the supply voltage inorder increase thze sound

[Ole Bauck]

Use a transistor, see here.

[MARTIN FR]

yes its a good option for me to test but i am looking for some smaller dimension component because my PCB is very small so i cannot able to affors that much big transistpr

[Ole Bauck]

A transistor can be very small, like the SOT-23 package. If the buzzer draws too much current from the gpio pin, the voltage will drop and so will the sound level. You can configure the gpio for high drive with this code:

NRF_GPIO->PIN_CNF[PWM_PIN] |= (GPIO_PIN_CNF_DRIVE_H0H1 << GPIO_PIN_CNF_DRIVE_Pos);

You should also rather sink current than source current, see here. This means the connection will be: VCC->BUZZER->GPIO